The batch copolymerization of tetrafluoroethylene (TFE) and copolymerizable fluorinated ethylenically unsaturated comonomers in the presence of a dispersing agent is known. However, it is desirable to improve upon this copolymerization by increasing the reaction rate and by incorporating greater amounts of comonomer into the copolymer.
Due to the higher reactivity of tetrafluoroethylene (TFE) compared to some comonomers, it has been difficult to achieve high levels of comonomer incorporation into melt-processible copolymers with TFE at reasonably rapid batch polymerization rates. Accordingly, the ability to incorporate more of such comonomers, particularly the comonomer hexafluoropropylene, into TFE copolymers is advantageous since certain resin physical properties are a function of comonomer content. Furthermore, it is desirable to produce TFE homopolymer and TFE copolymers of small particle sizes for certain applications such as coatings and the like.